domain

domain, in physics: see magnetism.

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(1) In a LAN, a subnetwork made up of a group of clients and servers under the control of one security database. Dividing LANs into domains improves performance and security.

(2) In a communications network, all resources under the control of a single computer system.

(3) On the Internet, a registration category. See domain name and Internet domain name.

(4) In database management, all possible values contained in a particular field for every record in the file.

(5) A group of end points (phones or gateways) in a SIP telephony environment. See SIP.

(6) In magnetic storage devices, a group of molecules that makes up one bit.

(7) In a hierarchy, a named group that has control over the groups under it, which may be domains themselves.

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1.	(networking)	domain - A group of computers whose fully qualified domain names (FQDN) share a common suffix, the "domain name". The Domain Name System maps hostnames to Internet address using a hierarchical namespace where each level in the hierarchy contributes one component to the FQDN. For example, the computer foldoc.doc.ic.ac.uk is in the doc.ic.ac.uk domain, which is in the ic.ac.uk domain, which is in the ac.uk domain, which is in the uk top-level domain. A domain name can contain up to 67 characters including the dots that separate components. These can be letters, numbers and hyphens.
2.		domain - An administrative domain is something to do with routing.
3.		domain - Distributed Operating Multi Access Interactive Network.
4.	(mathematics)	domain - In the theory of functions, the set of argument values for which a function is defined. See domain theory.
5.	(programming)	domain - A specific phase of the software life cycle in which a developer works. Domains define developers' and users' areas of responsibility and the scope of possible relationships between products.
6.		domain - The subject or market in which a piece of software is designed to work.